I read an interesting article some years back in a newsletter I used to subscribe to that was put out by Tuft's University (Catnip). I've noticed this to be quite true too. Perhaps the reason that beautiful Lizzie is standoffish, is because her dad was a very feral tom cat, as opposed to Robbie's dad. Several tom cats can sire one litter of kittens, and the study that Tuft's did found that kittens sired by feral males tend to be ice-princesses/princes, whereas tom cats that are friendly toward humans will sire friendlier kittens. Doesn't matter if they've never met the cat/cats, or interacted in any way...they tend to act more feral. Even raised inside, and handled from birth. That could be why Lizzie doesn't want the contact the way Robbie does. Hopefully that will change for the better after their spay/neuters.